File and method of making the same



Aug T10, 1937. l. s. RlPLE'Y 2,089,619

FILE AND METHOD OF MAKING THE SAME Filed Nov. 27, 1955 2 sheets-sheet 1Aug@ m9 1937. I. s. RIPLEY 2,089,619

FILE AND METHOD OF MAKING THE SAME Filed Nov. 27, 1935 2 Sheets-Sheet 2@i /jza /JL l., IMI' "l" I I III Patented Aug. 10, 1937 UNHTED STATESPATENT OFFICE FILE AND METHOD F MAKING THE SAME Application November 27,1935, Serial No. 51,960

13 Claims.

This invention relates to les and more especially to double-cut les andmethods of making them.

The general object of the invention is to provide novel and improvedfiles of this and similar types and also to provide new methods of filemanufacture whereby such les may be easily and economically producedeither by hand or by the employment of suitable machinery.

A more particular object of the invention is the provision in adouble-cut le of teeth of novel configuration which render the file moreefficient in operation and more adaptable in its utilization inconnection with shaping various kinds of material.

g3 noticeable in working on bronze, brass, and other so-called greasymetals and are also in evidence in cutting and shaping cast iron, toolsteel and other materials.

A further object of the invention is to provide a file of novelconstruction which will remove the material from the work in the form ofshreds instead of chips as in the case of an ordinary file of thepresent standard manufacture. Such shreds do not ll up nor clog thethroats between the teeth as rapidly as do the chips removed by means ofthe conventional double-cut illes.

In all of its preferred embodiments, my invention contemplates theprovision, in the approximately diamond-shaped or lozenge-shaped teeth 0of the double-cut files, of relatively slight grooves or scoringsextending in the general direction of the axes of the les. IIhesescorings or flutings appear plainly upon the backs of the teeth and alsomodify the effects of the over-cut and up-cut 15 so as to produceentirely new and improved types of cutting edges. These scorings may beapplied to the le blank at different stages in the manufacture of theles as will be fully disclosed as ,o the description proceeds.

Other objects and features of novelty, both with respect to the novelfiles and to their methods of manufacture, will be apparent from thefollowing specification when read in connection with the accompanyingdrawings in which certain embodiments of the present invention areillustrated by way of example.

In the drawings:

Figures 1-3 inclusive illustrate in various ways certain steps in themanufacture of a double-cut le in accordance with present practices;Figure 1 showing in plan a file blank which may be considered to havebeen ground and draw-filed preparatory to cutting the teeth; Figure 2 aplan View of the blank, showing diagrammatically the appearance of thele after over-cutting; Figure 2A a greatly enlarged fragmentarysectional view of one surface of the file taken on a line at rightangles with the over-cut; Figure 2B a similar View indicating thegeneral appearance of the le surface after stripping the over-cut; andFigur-e 3 showing somewhat diagrammatically the appearance of the filein plan after the superposition of the up-cut upon the over-cut;

Figures 4 7 inclusive similarly illustrate various stages of themanufacture of a double-cut file in accordance with one embodiment ofthe present invention; Figure 4 being a plan View of the ground anddraw-filed blank similar to Figure 1; Figure 5 being a plan view of theblank having the over-cut applied thereto as in Figure 2; Figure 6 adiagrammatic plan view of the over-cut blank with the scorings orgrooves superposed thereon; Figure 6A a fragmentary greatly enlargedsectional view of the file surface as indicated in Figure 6, taken on aline at right angles to the direction of the over-cut; Figure 6B a planview on the same scale of a portion of the le blank indicating theappearance of the surface of the file after the application of thegrooves or scorings to the over-cut somewhat more accurately than thediagrammatic showing in Figure 6; Figure 7 a diagrammatic plan view onthe same scale as Figure 6, showing the finished file after the up-cuthas been applied to the scored overcut surface; and Figure 8 is asomewhat diagrammatic plan view on an enlarged scale of a portion of acompleted ille such as shown in Figure 7;

Figures 9-12 inclusive are views similar to those in the precedingdescriptions illustrating another embodiment of the present invention;Figure 9 being a plan view of the uncut blank as in Figures 1 and 4;Figure 10 a diagrammatic plan View showing the blank scored or grooved;Figure 11 a similar diagrammatic view showing the scored blank with theover-cut applied thereto; and Figure l2 a diagrammatic plan view of thefinished le with both the over-cut and the up-cut applied to thepreviously scored blank;

Figure 13 is a view in perspective illustrating the operation of scoringor grooving the le blanks; and

Figure 14 is a View in transverse section of the scoring tool shown inFigure 13.

In order to particularly point out the present invention and todistinguish it from the ordinary double-cut files and the conventionalmethods employed in their manufacture, a short exposition of the priorart will be set forthfin connection with the first few figuresdesignated with the legends Prior art in the drawings annexed hereto.arermade are sheared from the metal sheets or bars and are then forgedand finally carefully and uniformly annealed. Then the surfaces of theannealed blanks are ground. After this, the blanks are finished by meansof draw-fllingin order to remove any unevenness left on the surface ofthe flle by the grindstone. In- Figure 1 the reference numeral Iindicates generally the plain le blank at this stage of the process ofmanufacture, the blank being provided with the usual tang Il. Thedraw-filing process may be done either by hand or by suitable machinerywhich automatically reciprocates a file of the proper constructionlongitudinally of the blank. After this operation, the over-cut isapplied as indicated at l2 in Figure 2 of the drawings,l usually bymeans of a broad chisel of special configuration.y This over-cuttingoperation produces the preliminary ridges or teeth M of the file blankeach having a sharp edge or burr l5, a front surface or rake I6 and backor clearance Il, as shown in the enlarged' fragmentary view of Figure2A. In the usual method of manufacture, the next step is stripping theover-cut, which is accomplished by reciprocating a le across the surfaceof the blank in the same Way as in theV initial draw-filing. This'serves to remove the sharp edges or'burrs I5 of the teeth'as shown at I8in Figure 2B of the drawings. Then the upcut is applied to the blank asindicated at I9 in Figure 3 of the drawings'. This operation serves tobreak up the long-ridges I4 comprising the initial teeth of the le intointersecting series of small substantially diamond-shaped teethlorscallops having converging cutting edges, as shown at 20 in Figure 3. Itwill be noted that the angle the up-cut makes with the axis of the fileis considerably smaller than that of the over-cut.

With this rsum of the prior art, the description of my improved filesand their methods of manufacture'will be readily understood. One of themost efficient embodiments of the'invention is illustrated in variousstages of manufacture in Figures 4-7 inclusivefof the drawings. Figure 4illustrates a blank 25 in the same state as Figure 1 after it has beenground and draw-filed. In Figure 5 the blank' 25 is represented ashaving applied thereto the over-,cut l2 and corresponds exactly to thestage represented in Figures 2 and 2A illustrating the prior art. Y

At this point, instead of stripping or again draw-ling the blank asshown in Figure 2B of the prior art disclosure, the sharp edges I5 ofthe preliminary teeth l5 are permitted to remain. Then the file blanks25 having the over-cut I2 thereon are scored along a multiplicity ofparallel lines extending generally in the same direction as the axis ofthe file.Y These lines are preferably parallel and thespacing'therebetween may vary within rather wide limits, but thestriations or grooves should preferably be close enough together so thatseveral of them take eiect on each of thesubsequently formed scallopsordouble-cut Ordinarily, the blanks from which the files aosae 19 teeth.The depth of these grooves 2T is readily appreciable with the naked eyekand should not be confused with the minute scratches which are Y .ormechanically. Preferably the grooves are formed in the blank by means ofa tool such as the one illustrated at 30 in Figures 13 and 14 f which isof triangular cross-section having the three cutting edges 3| eachprovided with a series f of triangular teeth or serrations 32corresponding to the shape and spacing ofV the grooves desired on thefile. In order to attain uniformity a preferred manner of execution ofthis step in the process is to place the iile blanks upon the bed of amachine similar to those employed in draw-iiling the blanks and securingthe tool Sil upon a reciprocating carrier similar to that used in thedraw-filing'operation. The tool is drawn back and forth across thesurface of the file until the scoring Z'I'is of the proper depth, inmost cases this depth being, as already indicated, less than that of theover-cut or the up-cut which determines the height of the teeth.

Other possible ways-l of cutting the grooves will suggest themselves tothose skilled in the art, and may include the use of straight orcircular knurling tools, a special presser foot attached to the cuttingmachine, an artificial abrasive tool, or an artificial abrasive groovedwheel, or in fact by the use of any type of machine which employs areciprocating tool or work carrier. Y Y

An approximation of the actual ap-pearance of the cutting surfaces ofthe le shown diagrammatically in Figure, 6 is presented in Figures 6Aand 6B. In Figure 6A the grooves l2i appear in the tops of thesingle-cut teeth i4 and also pass through the front face or rake of eachtooth. The scorings or grooves 2l extend along the backs or clearancesil of each tooth for a distance which depends upon the depth of cut ofthe grooves. It must be realized that the teeth as actually formed bythis operation will not be so geometrically perfect as suggested by theillustration in Figure 6A, but during the scoring process not only willsome of the metal be cut away from the teeth, but other portions of thesurface will be distorted and caused to ow and burrs will be formedadjacent the edges of the grooves 27. A fragmentary plan view ofthe'preliminary roughened teeth formed by the over-cut l2 and thesuperposed grooves 21 is shown in Figure 6B, which is also in somewhatdiagrammatic form.

' The next operation comprises applying the up-cut I9 to the file blank.This serves to break up the elongated, serrated single-cut teeth VI4into a multiplicity of intersecting series of lteeth or scallops 35which have ingeneral outline the typical configuration of the scallops2i] of the conventional leof the same grade. However, as will be clearlyseen from the enlarged View shown in Figure 8, each of these teeth islongitudinally striated, the cutting edges are serrated and their backsscored by the lines which remain from the cutting of the grooves 27after the application of the up-cut i9. Naturally the up-cut I9 causesthe metal of each tooth formed to flow together somewhat and has theeffect of not only closing or partially obliteratng portions of theover-cut, but also altering the-regularity of the scorings or grooves21.

It will be noted that the actual appearances of the teeth as shown inFigure 8 are quite diierent from the regular, unbroken scallops formedby the conventional methods, and that this difference is reflected ringreater eiciency, accuracy, and economy in the utilization of the newle. The spacing of the grooves 21 in most cases is different from thetransverse spacing of the intersections between the over-cut and theup-cut so that the actual shape of the finished teeth in lsuccessiverows along the file diers considerably. Some teeth will be intersectedat their apexes by one of the scorings 21 while others will be providedwith score lines upon the tapering side edges thereof, the cuttingpoints remaining as narrow, chisel-like edges.

Another embodiment of the invention is illustrated in Figures 9-12 ofthe drawings and shows the eiect of applying the striations or scoringsprior to both the over-cutting and up-cutting of the blanks. As before,the blank designated 40 in Figure 9 of the drawings has been ground anddraw-filed preparatory to cutting. In Figure 10 the blank 4|] has beenscored as at 21 directly after it has been smoothed by the draw-filingoperation. In Figure 1l the over-cut l2 has been applied over thescorings 2l and finally, as shown in Figure 12, the up-cut I9 has beenapplied. The teeth 45 in this ligure are of similar general outlines tothose shown at 35 in Figure 7 but are somewhat more sharply definedalong the right-hand edges due to the over-cut having been applied afterthe scoring. The file produced by serrating the blank rst, thenovercutting and up-cutting is equally as eiective as the one produced byserrating after the overcut and prior to the up-cut.

For certain other purposes, it may be desired to apply the scoring tothe file after both the over-cut and up-cut have been applied and thismethod and resulting article comprise still another embodiment of thepresent invention.

From these disclosures, it will be realized that by means of the presentinvention there have been provided novel and improved files and methodsof producing them which attain the stated objects in an eicient andeconomical manner; the principles of the invention being applicable todouble-cut files of various degrees of neness.

It is understood that various changes and modifications may be made inthe embodiments illustrated and described herein without departing fromthe scope of my invention as defined by the following claims.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

1. The method of making a double-cut le, which includes in combinationwith the teethcutting steps, the step which comprises forming in themetal of the working surface of the le a series of shallow grooves, saidgrooves extending substantially in the direction of the longitudinalaxis of the le and being of less depth than the height of the teethwhereby the resulting over-cut and the up-cut, and of less depth thaneither of said over-cut or up-cut.

3. The method of making a double-cut le, which includes in combinationwith the application of the over-cut and the up-cut, the step whichcomprises forming in the working face of the le a series of narrow,shallow, substantially parallel, closely adjacent scorings extending atan angle to both the over-cut and the up-cut, and of a depth of theorder of magnitude of approximately one-third of the depth of theovercut.

4. The method of making a double-cut file, which comprises the steps ofscoring the blank along a plurality of spaced lines extendingsubstantially in the general direction of the axis of the blank, thenapplying the over-cut, and then applying the up-cut, the scorings beingof less depth than either the over-cut or the up-cut.

5. The method of making a double-cut le, which comprises the steps ofapplying the overcut to the blank, scoring the blank along a series ofspaced lines extending in the same general direction as the axis of theblank, and then applying the up-cut, the scorings being of less depththan either the over-cut or the up-cut.

6. The method of making a double-cut le, which comprises the stepsof,applying the overcut to the blank, scoring the blank along parallel,closely spaced lines extending in the same general direction as the axisof the blank, and then applying the up-cut, the scorings being of lessdepth than either the over-cut or the up-cut.

'7. The method of making a double-cut file, which comprises the steps ofapplying the overcut to the blank to form a series of temporary teeth ofthe single-cut type, then serrating the edges of said temporary teeth,and then dividing the serrated teeth thus formed into series of jaggeddouble-cut teeth by applying the up-cut, the serrations being of lessdepth than said over-cut or up-cut.

8. The method of making a double-cut le, which comprisesythe steps ofapplying the overcut to the blank to form a series of temporary teeth ofthe single-cut type, then applying to the forward edges and backs ofsaid temporary teeth serrations of a depth less than the depth of saidover-cut, and then dividing the serrated teeth thus formed into seriesof jagged double-cut teeth by applying the up-cut.

9. The method of making a double-cut le, which comprises the steps ofapplying the overcut to the blank, then applying the up-cut thereto, andthen scoring the file along a series of closely spaced, substantiallyparallel lines extending in the same general direction as the axis ofthe blank, the scorings being of less depth than either the over-cut orthe up-cut.

10. A double-cut le having upon its Working face a plurality ofintersecting series of raised scallops forming the substantiallylozenge-shaped teeth of the conventional double-cut type, there being aplurality of generally longitudinally extending scorings on the workingface of said file, the spacing of the scorings being without regard tothe spacing of the intersections of the lines of over-cut and up-cut ofsaid file, whereby the teeth of the le are non-uniformly serrated.

ll. A double-cut file comprising teeth having the conventional,forwardly convergent cutting edges thereon, there being a plurality ofspaced scorings on said le, said scorings being of less depth thaneither the up-cut or the over-cut of the le, and the direction of saidscorings being at an angle to both the over-cut andl the uncut, wherebyboth of the convergent cutting edges of said teeth are provided withserrations.

12. A le of the type described having interseating series ofsubstantially pointedrteeth on its Working surface, therebeingsem-ations on the cutting edges and backs of said vteethlsad serrationsbeing of less depth than the height of said teeth. v ,e

` 13. A double-cut file having upon its Working face a plurality ofintersecting series of raised scallops forming the substantiallylozenge-shaped teeth ofthe conventional double-cut type, the cuttingportions of said teeth beingserrated, the serrations extending in thegeneral direction of the length of the file. y Y n l IRA S. RIPLEY.

